package LC;

/**
 * https://leetcode.com/problems/reverse-bits/description/
 * Reverse bits of a given 32 bits unsigned integer.
 * For example,
 * \given input 43261596 (represented in binary as 00000010100101000001111010011100),
 * return 964176192 (represented in binary as 00111001011110000010100101000000).
 * Follow up:
 * If this function is called many times, how would you optimize it?
 * Related problem: Reverse Integer
 */
public class LC_190_ReverseBits_BitManipulation {
    public static void main(String[] args) {
        int n = 43261596;
        System.out.println(Solution.reverseBits(n));
        System.out.println(Integer.toBinaryString(n));
        System.out.println(Integer.toBinaryString(Solution.reverseBits(n)));
    }

    static class Solution {
        static int reverseBits(int n) {
            int result = 0;
            for (int i = 0; i < 32; i++) {
                result += n & 1;
                n >>>= 1;
                if (i < 31) {
                    result <<= 1;
                }
            }
            return result;
        }
    }
}